Calculate Peak HorsePower and Torque

[MaxRaceSoftware]

If anyone is interested in calculating peak horsepower,
torque from their dragracing time slips;

Choose "one" of the following methods
that you have ET Time data for
Method 1) 60,660,1320 ET
Method 2) 60 and 1320
Method 3) 660 and 1320
Method 4) 1320 only

Additional need data from you ;
1) Car Weight Lbs. (w/driver)
2) Frontal Area Sq.Ft.
3) Cd Drag Coefficient
4) Type of transmission (Converter or Clutch)
5) Peak HP RPM-point ( or shift point?)
6) Wether you have a Hood Scoop or not

if you don't know frontal area sq.ft. or Cd
tell me what year car and make,model

i'll compute HP/Torque curve data and ET/MPH, GForces,
AeroDynamic HP Losses, Rolling Resistance HP Losses ,
Ram-Air Hood Scoop gains, ...each foot distance down 1/4 mile , and post short summary of run data Larry Meaux (meauxrace2@aol.com)
Meaux Racing Heads
MaxRace Software
ET_Analyst for DragRacers

 

[MaxRaceSoftware]

Actual DragStrip ET Slip data for ProStock Car

60 Ft= 1.020
330 Ft= 2.880
660 Ft= 4.420 - 160.000 MPH
1000 Ft= 5.770
1320 Ft= 6.870 - 200.000 MPH

Weight= 2360 Lbs. Cd=.30 FrontalArea=21.0 sq.ft.
Clutch with Hood Scoop 8900 =peak HP RPM
-------------------------------------------------

Computer generated;
64.7 HP from ram-air hood scoop

Peak HP=1255.1 Torque=807.3 (600 Rpm/SEC Acceleration)

Peak HP=1317.9 Torque=847.7 (Steady-State non-Acceleration)

Carb CFM=1642 to 1935 at 1.5 inches Hg.

Computer generated times;
60= 1.020 66.313 0 to 30 mph=0.303
330= 2.877 127.298 0 to 60 mph=0.872
660= 4.420 159.787 to 160.523 0 to 80 mph=1.365
1000= 5.746 185.964 0 to 100 mph=1.940
1320= 6.870 200.315 to 199.398 0 to 120 mph=2.608

Ft ET MPH
-1 - .145 0.000 = Rollout ET @ 12 inches
0 .000 9.428 = Rollout MPH @ 12 inches
1 0.086 12.777
2 0.131 17.160
3 0.167 20.225
4 0.199 22.697
5 0.228 24.812
6 0.254 26.681
7 0.279 28.369
8 0.302 29.915
9 0.325 31.348
10 0.346 32.687
...... and so on till 1320 ft Larry Meaux (meauxrace2@aol.com)
Meaux Racing Heads
MaxRace Software
ET_Analyst for DragRacers

 

[ivymike]

Out of curiousity, how does your model account for changes in tire radius as the run progresses?

 

[MaxRaceSoftware]

Out of curiousity, how does your model account for changes in tire radius as the run progresses?
---------------
i have another model that takes tire growth into account,
but in this model i tried to reduce the number of inputs to bare minimum

..you only need these inputs to come very ,very close
to HP/Torque figures

1) Car Weight Lbs. (w/driver)
2) Frontal Area Sq.Ft.
3) Cd Drag Coefficient
4) Type of transmission (Converter or Clutch)
5) Peak HP RPM-point ( or shift point?)
6) Wether you have a Hood Scoop or not

and "one method" such as ET data of any combination below;
Method 1) 60,660,1320 ET
Method 2) 60 and 1320
Method 3) 660 and 1320
Method 4) 1320 only


Larry Meaux (meauxrace2@aol.com)
Meaux Racing Heads
MaxRace Software
ET_Analyst for DragRacers

 

[evelrod]

Larry, try this one on for size, it was my best time back in '63.

Stock configuration 1961 Corvette,283 cu.in. 270 HP(prepared by Jack Moss Automotive), four speed(2,50 close ratio), 8 inch Bruce slicks, 4.88/1 limited slip.
Weight was about 2700 pounds I think, and I weighed in at 135 or so (200 these days!!!)
Time was 12.27 @ 105.57


Rod

 

[MaxRaceSoftware]

To anyone interested...
Send me a .JPG or .BMP picture of your race car or shop,
and i will digitally-enhance your picture and "included" inside the "ET_Analyst for DragRacers" computer program !
Also if you want it to appear along side your picture,
send me your shop or individual name, address, phone number
you want to appear inside program .

Till December 23, 2001 i will Email you back a .ZIPPED
program that you can run in Windows 3.11 on up ,
that will calculate more than i've been able to post in this forum ....the program will be absolutely FREE to anyone
till December 23, 2001 !! About a $ 90.00 dollar value for free to any Engine Tips Forum member .
This is a Windows .EXE program , and not a DOS-program.
Very easy to use and user friendly with plenty of HELP notes
including mouse arrow-scrollable graph of dragrace run
additionally, it will compute tire growth, gear ratio, converter/clutch lockup percent, engine rpm, etc.
Have a Merry Christmas , as we celebrate the birth of the Lord Jesus Christ Larry Meaux (meauxrace2@aol.com)
Meaux Racing Heads
MaxRace Software
ET_Analyst for DragRacers

 

[MaxRaceSoftware]

Out of the 4 ET data input methods,
the 60 Ft, 660 Ft , 1320 Ft ET Times inputted
will result in the most accurate HP and Torque figures

the least accurate method is to use the "single" time
that being the 1320 Ft Elapsed Time only
i know back in 1961 there weren't any 60 Ft, 330 Ft,
660 Ft, 1000 Ft ETdata generated by clocks
back in those days ..only the 1/4 mile 1320 Ft ET and MPH
so the HP and Torque calculations will be the least
in accuracy of the 4 methods .

To get "dead-on accuracy" which is about +- 5 HorsePower or better
of actual dyno test results.....i would need more accurate input
such as the 60 Ft , 660 ft , and 1320 Ft ET times to the
thousandths of a second....and accurate total car weight lbs.,
accurate Frontal Area sq.ft, Cd drag coefficient (hard to obtain)

i guesstimated the 1961 Corvette frontal area at 21.0 sq.ft
and the Cd at .38 , the frontal area might be 1 or 1 1/2 feet
too large at 21.0 ??, but you had side mirrors ?
convertible or not ?? if convertible, was top down or not ??
Not clear what to input ?? so i guesstimated !

You weren't clear to car weight , if the weight =2700 lbs.
included the 135 lbs. driver or not ???

So if total car weight with driver = 2700 lbs,
and no ram-air hoodscoop, with maual transmission,
RPM of peak HP was at 5500 then.....you made

Peak HP=240.6 Torque=250.4 (600 RPM/SEC Acceleration)

Peak HP=252.6 Torque=262.9 (Steady-State non-Acceleration)

Carb CFM=315 to 371 at 1.5 inches Hg.

Ft ET MPH
60= 1.651 38.854 0 to 30 mph=1.043
330= 4.923 70.709 0 to 60 mph=3.614
660= 7.731 87.158 to 86.092 0 to 80 mph=6.264
1000= 10.179 100.286 0 to 100 mph=10.112
1320= 12.270 107.434 to 108.764 0 to 120 mph=13.640

Ft ET MPH
-1 - .234 0.000 = Rollout ET @ 12 inches
0 .000 5.824 = Rollout MPH @ 12 inches
------------------------------------------------------------------------------

if total car weight was = 2835 lbs. with driver then you made

Peak HP=249.2 Torque=259.4 (600 RPM/SEC-Acceleration)

Peak HP=261.6 Torque=272.3 (Steady-State non-Acceleration)

Carb CFM=326 to 384 at 1.5 inches Hg.

FT ET MPH
60= 1.651 38.854 0 to 30 mph=1.043
330= 4.923 70.709 0 to 60 mph=3.614
660= 7.731 87.158 to 86.092 0 to 80 mph=6.264
1000= 10.179 100.286 0 to 100 mph=10.112
1320= 12.270 107.434 to 108.764 0 to 120 mph=13.640

Ft ET MPH
-1 - .234 0.000 = Rollout ET @ 12 inches
0 .000 5.824 = Rollout MPH @ 12 inches

the reason the MPH= 107.434 to 108.764 instead of
105.57 MPH you actually ran is this= you have to
enter 60 Ft and 660 Ft ET data to get the 1320 FT
MPH to correlate better ..then everything else will
correlate better . also if you made the
above runs with the top down on a convertible,
the CD would increase, and the HP/Torque would
increase closer to the 270 HP figure
it would be interesting to see what the actual
shipping weight of a 1961Corvette is ?
at 3000 lbs. with a driver , 12.270 ET would equal
273 HP at steady-state dyno test


Larry Meaux (meauxrace2@aol.com)
Meaux Racing Heads
MaxRace Software
ET_Analyst for DragRacers

 

[evelrod]

Thanks , Larry. We did some 0-60 tests once and they were sub 4 seconds. The weight of the Vette was as produced including driver with hardtop installed minus soft top and hardware and, minus spare and tools. Otherwise stock as it ran in a D Stock Sport class then. On the dyno for breakin and a short test run, it made 290hp.corrected to sea level. The altitude at Amarillo, TX is about 3900ft. if memory serves me. All this is from memory so it may be a little off. We all get faster and better drivers as we get older and farther away from the facts. It is interesting to see how far we have progressed, eh?


Rod

 

[MaxRaceSoftware]

Amarillo, TX ...there was an engine builder back then that was pretty famous named Carrol Claudle ??
i think he also ran a Vette ??
Larry Meaux (meauxrace2@aol.com)
Meaux Racing Heads
MaxRace Software
ET_Analyst for DragRacers

 

[GaugeGirl]

Larry,

Did you have a display at the PRI show this year?

 

[MaxRaceSoftware]

Larry,

Did you have a display at the PRI show this year?
-------------------------------------

No..but i had planned to go this year and at the last minute
i couldn't make it

Next year , i will be there .

i have a friend that "drives" to Indy and setups up a display ..he won't never fly !

He says if you hear of me getting in a plane crash...
it wasn't me !!!!

He says "About the only way i would be in a plane crash, was if it crashed into my house or my car while i was driving ."


Larry Meaux (meauxrace2@aol.com)
Meaux Racing Heads
MaxRace Software
ET_Analyst for DragRacers

 

[GaugeGirl]

This year's show was great. Many manufacturers released new products. The products available to the average guy now are incredible. I was extremely impressed with the various data acquisition systems introduced/ updated. As I mentioned in another post as well, the products released for the import market, made a big impact on the show this year. Do you have any thing set up for them and the crazy combinations they are running? The import youngsters are pretty computer savvy...

 

[MaxRaceSoftware]

Do you have any thing set up for them and the crazy combinations they are running? The import youngsters are pretty computer savvy... -GaugeGirl

No..i know theres are fast growing import market
but with the front-wheel drive cars , computers,
wiring harnesses, ETC. ....it makes it extremely difficult
to remove everything and setup on a dyno like mine
...so the future looks pretty good for chassis dynos
to a point for those racers , the serious racers will
still tune on an engine-stand type dyno /and or both.

and you are correct..that these youngsters are computer savvy....makes you wonder how these racers know so much so soon in life ??

i quit doing complete engines...and just concentrate
on Balancing, Porting, and Dyno Testing
just do Ford, Chrysler, and GM heads ..don't have time
to do motorcycle or import style heads..even though i get a bunch of requests Larry Meaux (meauxrace2@aol.com)
Meaux Racing Heads
MaxRace Software
ET_Analyst for DragRacers

 

[MaxRaceSoftware]

Carb CFM=326 to 384 at 1.5 inches Hg.

Rod..i just noticed the required minimum carb CFMs
..did you have a Rochester 4GC carb back then on your 61 Vette ? or was it a Holley or Carter AFB back then ?

Power Pack heads with 1.720 / 1.500 valves ? Larry Meaux (meauxrace2@aol.com)
Meaux Racing Heads
MaxRace Software
ET_Analyst for DragRacers